Plasticized aminoplast



radicals, or one selenium, =NH, etc. g I

the aryl compound is that it contain at least one,

N-substituted (partlyor completely substituted-l or N-unsubstituted amido radical and that in the Patented Sept. 16, 1941 2,256,278 I rmsncrzap AMINOPLAST Gaetano r. DAlelio, manna, Masa, mm... to General Electric Company, a corporation of New York No Drawing. Application December 24, 1940, Serial No. 371,584

14 Claims.

This invention relates to new and useful compositions having properties that render them particularly useful in the plastics and coating arts. Specifically the invention is concerned with compositions of matter comprising an aminoplast (more particularly heat-curable and heat-cured aminoplasts) modified, specifically plasticized, with a nitrogenous compound selected from the class consisting of (1 aryl compounds having attached to the aryl nucleus at least one amido radical and at least one radical containing the essential unit radicals and one, two or three rtr radicals, or one amido radical and'one to five at-ti e.

radical and one to five amido radicals. Theunsatisfied single valencies in the described radicals may be satisfied by hydrogen or any monovalent and in the amido radical may be satisfied by a divalent atom .or radical, e. g., oxygen, sulfur, The only requirement of other above-identified essential radical there be an aldehyde. e. g., formaldehyde, and therefore can intercondense under heat with the other components of the aminoplast (or with the partially formed aminoplast) thereby to become an integral part of the resinous mass.

As is well known, aminoplasts are synthetic resins derived from amino (including imino) or amido (including imido) compounds, a typical example being urea-formaldehyde resin (reference: Modern Plastics, vol. 17, No. 2, October. 1939, page 433; U. S. Patent 2,214,851, DAlelio). Otherv examples of aminoplasts are aminotriazinealdehyde resins (e. g., melamine-formaldehyde resins), urea-aminotriazine-aldehyde resins, aminodiazine-aldehyde resins, protein-aldehyde resins (e. g., casein-formaldehyde resins), anilinealdehyde condensation products, benzene disulfonamide-aldehyde resins, sulfanilamide-aldehyde resins, resinous condensation products of aldehydes such as formaldehyde with polyamides as, for instance, malonic diamide, maleic diamide, fumaric diamide, itaconic diamide, etc. Such products in partly condensed state are potentially thermosetting compounds-and, in cured or heathardened state, may be ejected from hot molds.

In the commercial utilization of aminoplasts in the plastics and coating arts, it is frequently necessary to modify the potentially heat-curable aminoplast by incorporating therein a plasticizer in order that the aminoplast will flow properly in the particular coating composition or, in the case of thermosetting aminoplast molding compositions, will show good flow characteristics during molding. If improper or insufficient plastic satisfied double valency'of the carbon atoms in and- ,atj'elevated temperatures and should no "bleed" from the aminoplast during or after flow occurs during the molding operation, the molded articles may show streaked or wavy surfaces. Eurthermore, if the plasticity of the molding composition is not sufficient, lack of physical homogeneity as the result of incompletely knitted granules often characterizes: massive-moldings.

From the foregoing it will be seen that par ticularly in the molding of heat-curable, plasticizedaminoplastsit is important that the plasticizer have certain physical characteristics. It should improve the flow of the molding compound "during molding without retarding the curing of the resin at molding temperatures. It should b compatible withthe aminoplast both at. normal molding. Itshould not discolor, "oi-impart an v odor to, or lessen the water resistance,,.electric al properties, mechanical strengthandother useful properties of the cured aminoplast. The substances that-are able to meet these. requisites are .eirtremely rare.

Urea and various substituted wear, phenols, aniline, toluene sulfonamides and result of which the compounds are reactab'le with cold bodies heretofore have been used or sug-- gested as plasticizers for janiinoplasts, but none 2 has been entirely satisfactory. In most cases the improvement in plasticity was attained at the sacrifice of some other useful property. For example, the addition of the ordinary ureas (e. g.,

NHaCONHz) decreases the water resistance of the molded article, Phenols impart color and odor, while aniline not only imparts co1or and v radical and at least one radical containing the essential unit mi t 5 m and aldehyde reaction products of such aryl compounds constitute a class of materials that meetthe above-mentioned requirements for a plasticizer for aminoplasts. These organic compounds not only efiectively plasticize the heatconvertible aminoplasts so that the aminoplast has good flow characteristics during molding, but they accomplish this result without retarding the curing of the aminoplast during molding. Furthermore, the aminoplast is internally plasticized without any noticeable decrease in the other valuable properties of the heat-hardened aminoplast, such as heatand water-resistance, dielectric strength, mechanical strength, surface appearance, color, odor, etc. Another advantage accruing from the use of these organic compounds is that they are able to intercondense with the potentially reactive aminoplast and, there fore, cannot bleed from the molding composition or the 'molded article since they become an integral part of the resin molecule. Also, larger amounts pf plasticizer can be tolerated in the compositions than usually has been possible with otherwise plasticized aminoplasts, and yet not HzNCONH-CHaNH-CsHc-OH are entirely unsatisfactory, since not only do they cause serious discoloration but also cause a material decrease in the water resistance of the fin- 1 ished molded or laminated article.

The organic compounds with which amino-. ,plasts are plasticized in accordance with the present invention may be described more particularly as compounds having the graphic formula v represents a mono or poly aryl nucleus, e. g., benzene, haiog'eno-aryl (e. g., halogeno-benzene) alk'ylated aryl (e. g., alkylated benzene), hydroxylated aryl (e. g., hydroxy benzene), alkoxy 5 aryl (e. g., alkoxy benzene), aryloxy aryl (e. g., phenoxy benzene), acetox'y aryl (e. g., acetoxy benzene), carbalkoxy aryl (e. g., carbalkoxy ben zene), arylated benzene (e. g., phenyl benzene), naphthalene, etc. B may be either hydrogen or a monovalent organic radical, .more particularly a substituted or unsubstituted hydrocarbon radical, e. g., aryl, aralkyl, alkyl, alkaryl, acyl, naphthyl, hydrocyclic, heterocyclic, etc., radicals, or nitro, halogeno, carbalkoxy, acetoxy, amido, imido, amino, nitrilo, etc., derivatives of such radicals. I prefer to use compounds wherein R represents hydrogen. Y may be a divalent atom or radical, examples of which have been given heretofore with reference to the unsatisfied double valency of the carbon atom to which Y is attached, but preferably is either oxygen or sulfur. In Formula II n and n are integers and are at least 1, the sum of n and n varying from 2 up to the combining power of the particular aryl nucleus.

More specific examples of compounds comprising the plasticizers used in carrying the present invention into eifect are listed below:

o NmcoNa-omNn-Q-i-mrcnmnc 01m,

Ha I Additional examples of compounds that may be employed are the aldehyde, specifically formaldehyde, reaction products of compounds such as abovementioned by way of illustration and wherein the =NH, r

or NH: groups are converted into alkylol, speciflcally methylol, derivatives, e. g., =N- CBzOR, or alkylene, specifically methylene. derivatives, e. g., N=CR:, where R is hydrogen, alkyl, aryl, etc. Other examples of compounds that may be employed are compounds similar to those mentioned in the above list but differing therefrom in that, instead of the oxygen atom in the groupings the sulfur atom or the imino (=NH) grouping,

for example, is substituted therefor in one or all such and the aldehyde reaction products of such compounds.

A further advantage accrues from my invention when certain particular compounds are employed. For example, compounds of the class exemplified by the specific examples marked with an asterisk in the above list are able not only effectively to plasticize the composition but also function as curing .reactants, that is, their incorporation into the resin or a molding composition prepared therefrom accelerates the conver- -sion under heat of the heat-convertible aminoplast from a soluble, fusible state to-an insoluble,

infusible condition.

' Example t ,A heat-convertible. molding composition com active urea-formaldehyde partial condensation wherein thedescribed plasticizer was omitted from the formulation. In all cases, better knitting and fusion took place and there was higher plastic flow per unit time in compositions containing the plasticizer as compared with the plasticizer-free composition. Furthermore, there wasno decrease in the water resistance of the molded article prepared from the described plasticized aminoplast.

In a specific case wherein 5% by weight the compound) of was incorporated into a filled, plasticizer-free tests.

other hand, showed excellent plastic flow during molding and yielded molded articles that were well knitted or fused together into a strong molded piece of excellent surface characteristics.

Substantially the same results, as above described, are obtained when molding compositions comprising potentially reactive, filled melamineformaldehyde and melamine-urea-formaldehyde resins are substituted for the filled urea-form -aldehyde molding composition.

More specific examples of aminoplasts which may be plasticized with the hereindescribed plasticizers are reaction products of an aldehyde, forexample formaldehyde or compounds engendering formaldehyde (e. g., paraformaldehyde, hexamethylene-tetramine, etc.), with amido, imido, amino or imino compounds, or suitable mixtures thereof, for instance urea, thiourea, diurea, hy-- droxy urea, ethanol .urea, unsymmetrical di- 'phenyl urea, diethylene triurea, methyl urea, acetyl urea, phenyl thiourea, asymmetrical diproduct, a small amount of a curing reagent and 35-45 p'arts alpha cellulose in flock form ..were dried and ball milledwith from 2 to "10 parts of a compound of the formula in the presence of the usual m'old lubricants,

dyes, etc. The finely ground-powder -was densi-- fied in the usual manner and molded at to C. under a pressure of about 2,000 pounds,

per square inch. In a similar way molding compositions and molded articles were prepared ethyl urea, allyl urea, 2'-chloroallyl urea, ethyl idene urea, methylol ureas, methylene 'ureas, etc.; also, other members of the urea system as, for example, guanidine (iminourea), dicyandiamide (cyano-iminourea), guanyl urea, guanyl thiourea, biguanidine, aminodiazines, aminotri- .azines, aminopentadiazines, creatinine, guanoline, etc. -.In many cases the use of an aminotriazine, e. g., melamine, alone or in conjunction with other amido, amino, imido or imino compounds, yieldspar'ticularly valuable amino-" 0' prising 55-65'par'ts by weight potentially re-' plasts which may be internally modified in accordance with the present. invention. Illustrative examples of aminotriazines (amidogentri- -azines) that may be employed are given in various copending applications of mine, for examplein copending application Serial No, 365,379, filed November 12, 1940, and assigned -to.the same assignee as the present invention. Suitable mixtures of .aminotriazines also may be employed. All of these ar'nido, imido, amino and imino compounds are aldehyde reactable and all at least one active group.

; Aldehydes other than formaldehyde or so contain pounds engendering formaldehyde also may be employed in producing the aminoplast, for instance acetaldehyde, propionaldehyde, butyral- 'dehyde, acrolein, methacrolein, crotonaldehyde,

or an aminotriazine (e. g., melamine) and form-.

aldehyde, or urea, melamine and formaldehyde. The hereindescribed plasticizer reactant or modifier may be incorporated into the resin along with the other reactants, or during or after formation of'the partial condensation product, or during the preparation of the molding composition. For example, the plasticizer component may be incorporated into the resin or molding composition as described more specifically in, for example, my copending application Serial No. 346,962, filed July 23, 1940, with particular reference to suitable technique for incorporating a' malonic ester into an aminoplast composition. The potentially heat-convertible aminoplasts and molding (moldable) compositions containing the same may be prepared as described in the above-identified copending application and in various other copending applications, for example application Serial No. 363,036, filed October 26, 1940, and assigned to the same assignee as the present invention,

The amount of plasticizer reactant which is incorporated into the potentially reactive aminoplast or molding composition made therefrom may be varied as desired or as conditions may require, but ordinarily is employed in an amount corresponding approximately to from 0.1 to 10 or 12% by weight of the aminoplast, from 0.5 to 4 or being generally satisfactory for the usual aminoplasts.

Thermosetting molding compositions comprising potentially heat-curable aminoplasts plasticized with the plasticizer reactant herein described may be molded into a variety of shapes under heat and pressure, more particularly at temperatures of the order of 100 to 200 0., preferably from approximately 120 to l80 C. The plasticized compositions show good plastic flow during molding. 1 Molded articles of manufacture comprising the molded heat-hardened molding compositions of this invention have a good surface finish, show no evidence of bleeding plasticizer, are well cured throughout, and show no appreciable loss in any of their other useful properties due to the presence of the plasticizer comprising either (1) one or. more aryl compounds having attached to the aryl nucleus at least one unsubstituted or partly or completely substituted amido radical and at least one radical containing the essential unit (2) or one or more aldehyde reaction products of the aryl compounds of (1), or both the compounds of (1) and (2).

What I claim as new and desire to secure by Letters Patent of the United States is:

' nucleus at least one amido radical and at least one radical containing the essential unit I (HN ,1 I- :N- and (2) aldehyde reaction products .of the aryl compounds of (1).

.2. A composition. of matter comprising anv aminoplast modified with a mono-aryl compound having attached to the aryl nucleus at least one amido radical and at least one radical containing the essential unit B tman 3. A composition of matter comprising an aminoplast modified with. an aldehyde reaction product of a mono-aryl compound having attached to the aryl nucleus at least one amido radical and at least one radical containing the essential unit m leage. 4. A composition of matter comprising an aminoplast modified with a mono-aryl compoundhaving attached to the aryl nucleus at least one amido radical and at least one radical having the structure -NHCH2NHCONH2.

5. A composition of matter comprising an aminoplast modified with a mono-aryl compound having attached to the aryl nucleus a single -CONH2 radical and a single NHCH2NHCONH2 radical.

6. A heat-curable resinous composition comprising a potentially reactive aminoplast modified with a nitrogenous compound selected from the class consisting of (1) aryl compounds having attached to the aryl nucleus at least one amido radical and. at least one radical containing the essential unit I heat-hardened molding composition of claim 8.

10. A composition comprising a condensation product of ingredients comprising urea and formaldehyde, and a modifier of said condensation product comprising an organic compound having the formula 11. A composition comprising a condensation product of ingredients comprising urea, melamine and formaldehyde, said condensation product being modified with an organic compound having the formula y N HzCON HCH2NHCsH4CONH2 12. A composition comprising a condensation product of ingredients comprising urea and formaldehyde, and a modifier of said condensa- 2,256,278 tion product comprising an aldehyde reaction product 01f formula NHaCONH-CHaNH-CeI-Iw an organic compound having the CONHCI-IaCI-IzNHOCCHzCl v 14. The method or plastlcizing an aminoplast which comprises incorporating into the potentially reactive aminoplast under heat a nitrogenous compound'selected from the class consisting of (1) aryl compounds having attached to the aryl nucleus at least one'amido radical and at least one radical having the unit structure and (2) aldehyde reaction products of the aryl I compounds of (1).

GAETANO E. DALELI 

